savata71

Yes, of course – I saw it now. It is absolutely simple. And I am trying swim in deep waters…

Yes, if we use the law of conservation of energy. The potential energy in highest position is equal to kinetic energy in starting position. That way it can be solved without differential equation, indeed.

For #1 and #2 watch Lec 8 | 8.01 Physics I: Classical Mechanics, Fall 1999: http://www.youtube.com/watch?v=uZGbtK2KBoY and you will do them #3 is much harder for understanding and solving - you have to pass through examples for how similar problems are solved.Because differential equations and integrations are involved.

ok, i understand

Ok, maybe the time is enough. Now I am checking it.

The time here is not enough. Mass does't matter but you need a starting (initial) velocity to solve jump height. I will try to write how it solves after consulting with my books.

The question about Newton’s laws and how they appear, especially when we talk about gyroscopes, is too hard for me. There are many things involved here. I just have to learn more. For now I can give advice to those who will make computer simulations (like sterologist said before): You saw how I made mistake in my suppositions and how simulating software confirm these wrong suppositions (unbelievable coincidence of mistakes). So, be very careful when you make deductions based on computer simulations!

But what changes it? - The reaction. And what the Law says? - For every action there is an equal and opposite reaction. If the reaction was opposite there would be no change in direction. P.S. Ok I wrote it too fast... I am thinking now if the changeing of direcion of toorque means that the reaction is not opposite in every moment of time...

Ok, I will try to understand the difference. In Bulgarian there is only one word for speed (or velocity) I think ...

Well, I can’t see the reason why torque not to be constant during precession. The magnitude of torque has influence on the speed of precession but this speed is constant. Gyroscope just has strange reaction on torque. And this reaction is a criminal – it rudely breaks Newton’s laws: Let’s imagine a stone with a gyroscope inside and we don’t know that. The gyroscope inside have constant angular velocity. And let’s imagine that we are in space without gravity. 1. Now there are no outside actions and noting happened – first Newton’s law is satisfied. 2. We decide to action on that stone with a constant torque (with two small jets for example) and, according to Newton’s second law, we expect this stone to start rotation with increasing angular velocity (angular acceleration). But stone respond us with rotation where angular velocity is constant. The second Newton’s law is broken. 3. According to Newton’s third law we expect equal and opposite reaction but what we find? Reaction in another direction. The third Newton’s law is broken.

It will be easier if the bullet have a form of boomerang.Then you can shoot round the corner:-)

Ok, I understand that I have to push something to get its reaction to push me, but by the same reason I can get a torque without being on a surface and there is no need to block the rotation to have a torque – if I rotate something it rotates me but there is a torque. So, this device could work if precession was a linear motion, but not angular. I can’t answer to the question how is linear momentum being conserved here, because I don’t think that this device will work (for the present:-)), but the things are not always so clear. What will you say about that: While a torque acts on an object (gyroscope) the result is a CONSTANT angular speed motion (precession). Instead of: While a torque acts on an object the result is ACCELERATING angular speed motion.

Yes, to my regret I think you are right … Maybe something wrong happen with the simulating software when I transfer the models from Solid Edge to Parasolid and then to Visual Nastran. I will try to make the model directly in Visual Nastran to see what will happen. Merged post follows: Consecutive posts merged Well, I thought that a tendency for precession which will appear in response to a motor torque (and which starting direction is UP) can oppose to gravity, but now I am very hesitate in my opinion.

There are known rules how to find in what direction the precession appears. I can't explain it in English now (I'm not sure that I can do this in Bulgarian too), but if you see this ocular demonstration http://www.youtube.com/watch?v=8H98BgRzpOM&feature=related you will agree with the smaller scheme in my previous post. The bigger scheme derives directly from the smaller.

If you ask me – I don’t know the equation. Here is my reason to believe. I hope you can read from picture. I just check this with the simulating program. If this reasoning is wrong, where is the mistake?